In the existing pulsator washing machines, an inner tub and an outer tub communicate with each other through drainage holes, the inner tub is a washing tub and the outer tub is a water containing tub. The part of water filled in the space between the outer wall of the inner tub and the inner wall of the outer tub is not used for washing, only the water inside the inner tub is genuinely used for washing and the water resources are wasted. In addition, too much water between the inner and outer tubs reduces the concentration of detergent in the washing solution. At the same time, as the water flow constantly flows in and out between the inner tub and the outer tub, the space between the inner tub and the outer tub becomes a place for hiding filth after continued use. The scale of the tap water, the free powder of the laundry, the cellulose of the clothes, the organic matter and the dust and bacteria brought into by the clothes are easily left on the walls between the inner and outer tubs. These molds are bred from the accumulated large amount of dirt which is not effectively removed in the long used washing machine. If this dirt which cannot be seen by users stays inside the washing machine, these bacteria will adhere on the washing laundry during the next washing and cause cross-contamination problems to users.
The patent No. 201210011789.1 relates to a sealed inner tub comprising side wall and bottom which are integrally connected, and the side wall and bottom are provided sealed. A drainage recess is provided at the top of the side wall, and the water in the inner tub and the water in the laundry are discharged outside the inner tub through the drainage recess. The patent further relates to a washing machine with the sealed inner tub and a washing method of the washing machine. With the design of no holes on the inner tub, the purpose of saving a lot of washing water can be realized by preventing the washing water from entering the space between the inner and outer tubs. At the same time, the dirt and bacteria between the inner and outer tubs does not come into contact with the clothes in the inner tub through water flow which is effectively preventing cross-contamination of bacteria and makes the washing machine more health, environmental protection and safety. However, all the water is discharged from the top, and the line debris, sediment and other dirt in the water cannot be completely discharged, the remaining dirt will cause contamination to clothes during next washing.
The patent No. 200420107890.8 relates to a full-automatic washing machine which comprises a housing, a washing dewatering tub, a water containing tub and a driving device. The water containing tub is mounted outside the washing dewatering tub and fixed connected to the housing. A sealing means is provided between an inner bottom of the water containing tub and an outer bottom of the washing dewatering tub and a sealed chamber is form inside the sealing means. No through holes are on an outer side wall of the washing dewatering tub and a drainage hole is communicated with the sealed chamber is provided at a bottom of the washing dewatering tub. A first drainage hole communicated with a drainage pipe is provided on the water containing tub and a drainage valve is provided on the drainage pipe. The water containing tub is fixedly connected to the housing by a boom. One end of the boom is connected to an inner wall of an upper portion of the housing, the other end of the boom is connected to an outer wall of the water containing tub. However, the sealing means is easy to leak with long time operation and abrasion and if the water quality is poor with high sediment concentration, the service life of the sealing means will be significantly reduced, so the proper function cannot be played. It is not suitable for use in a state where the washing capacity is large, and the reliability is poor.
As a preferred scheme, a row of drainage holes is not provided at a center part of a bottom of the inner tub but provided at a side part of the bottom of the inner tub, and the control mechanism of the drainage holes is provided at a bottom of the outer tub. However, if the drainage holes are provided at the side part of the bottom, the inner tub needs to be positioned at every end of the dewatering process or at every start of the water supply of washing process as the inner tub rotates. Thus, it ensures the alignment between the drainage holes of the inner tub and the control mechanism of the drainage holes of the outer tub.
In the view of foregoing, the present disclosure is proposed.